C5kid

I was looking at the post that Andy from A&A put up about forced induction cars really picking up the power by putting a stock 06 Z06 cam into their car.

Does anyone know the specs of the cam? I already have a SLP cam w/ better lift and duration and wanna see if it will be worth the time and money to put this in.

Thanx

double06

210 / 230 at .050 lift
276 / 295 at .006 lift
.591 lift
LSA 120 degrees

427CPE

how much ground in advance?

vertC6

I am a little confused, how are the numbers at .006 so high compared to the .050 numbers. My calculations show the .006 to be at 262/282 what am I missing? Are they different on 1.8 rockers? Thanks

double06

The duration I got out of a magazine. The .006 depends on the ramp so the factory may have a nice long ramp vessus other cam manufacturers that have lesser ramp duration. My Comp Cams is 50 degrees above my .050 numbers 236 / 285 at .050 / .006.

Not sure what advance they install cam at did not mention that. Also looks like the closing side of lobe is slower than opening probably for longer lifter life.

At .006
Open Close
Intake 8 BTDC 89 ABDC 277
Exhaust 80 BBDC 35 ATDC 295

At .050
Open Close
Intake 18 ATDC 49 ABDC 211
Exhaust 52 BBDC 2 BTDC 230

dgdoc

How do you like your Comp Cam?

vertC6

I haven't actually bought a cam yet from comp, I just had one of their lobe charts that shows the duration and lift of cam at .050 and what the coresponding .006 number is and it was way off of the Z06 cam specs. I thought that the numbers were related to one another, obviously not. Its mind boggling to try and figure out cams, there is just so much more than meet the eye.
I am actually going to build a blower car and I have seen great results with the c6 z06 cam in LS1's and 2's. Just trying to figure out all of the cam specs so I can figure my DCR. I am afraid this cam may drop it below what I want with the high LSA. Thanks for the info.

dgdoc

Sorry for the confusion - I was asking Double06 how he liked his Comp Cam.

Comp is a good company and if you give them a call, they should be able to help you with recommendations for a blown application.

glass slipper

Ahhh, I see the problem now. You're assuming all "advertised" duration numbers are taken at .006" lifter lift. (And since it's at lifter lift, rocker arm ratio won't affect advertised duration specs to answer your question from above.) Comp Cams is the only one I know of that uses .006" (not saying they are the only one) while most cam companies use .004" and GM uses .002". That's why you'll see GM advertised duration numbers much higher than others. In the days when more duration meant a better cam, cam manufacturers would use whatever they wanted to inflate their numbers over others. To aleviate the "cheating", the standard of .050" lifter lift is used so the consumer can compare apples to apples when looking at duration.

Of course, as you've already probably figured out, this makes comparing DCR impossible when you're using the closing point of the intake valve if you're looking at two cams made by different manufacturers with one using .002" (GM) and the other using .006" (Comp Cams) for their "standard". And since the opening/closing ramps are long (compared to the rest of the lobe), a .004" difference in lifter lift will make a significant difference in the intake valve closing point/DCR calculation. Which brings me to another point...don't get too caught up in the DCR number. I doubt with the intake .050" duration spec of 211 degrees that DCR will drop too low over the stock cam even with 120 LSA...the LS2 duration/LSA specs really aren't too far off from the LS7 numbers. You can make up some of the loss down real low with more timing and remember (in NA applications) DCR will equal SCR at about the RPM at which peak torque occurs...with good heads, it's all gains from there on up. If others are using the LS7 cam with good results, don't try to reinvent the wheel unless you have $$$ for many cam changes...until you find out the LS7 cam is the best.

vertC6

Thats exactly what I was thinking, thanks for the great post. Trying to figure out the numbers of (GM's) specs, vs. the other numbers I had from comp I knew something wasn't right. My thinking was just go ahead and have comp make me a cam with the same overall specs, maybe bring the LSA to 118.5 and add 2 degrees of timing. Otherwise I would need a variable cam gear to adjust the timing which is 150 bucks, so why not just have comp make one. What do you think GS? I know the stock LSA on a LS2 is 116 on a 204 intake, if I am able to figure out what the true numbers are on the LS7 cam then I can figure out my DCR, but you are probably right it should not change too much. With the numbers that I had put into my calculator the DCR was 7.9:1 as compared to the stock LS2 is 8.56 DCR, but once again I think my .006 numbers are wrong. My goal is to keep the DCR in the low 8's.
I need to get you on the phone sometime pick your brain, you are definitely the athority on cams. Thanks for the help.